1. CMPE 118 MECHATRONICS Digital I/O Transistors and Mosfets

2. CMPE 118 MECHATRONICS Bipolar Transistors used as Switches NPNPNP Base Emitter Collector Emitter How do we get them turned on? Forward bias the Base:Emitter Junction Supply current How much current? 1/10th as much as the Collector:Emitter current How do we know if we have been successful? V ce will drop to about 0.2V

3. CMPE 118 MECHATRONICS Bipolar Transistors used as Switches How do we get them turned on? How do we know if we have been successful?

4. CMPE 118 MECHATRONICS MOSFET Transistors used as Switches N-Channel P-Channel Gate Source Drain Source Drain How do we get them turned on? |V GS | > Threshold N-Channel: G > S, P-Channel G < S How do we know if we have been successful? R DS will drop to a low value

5. CMPE 118 MECHATRONICS MOSFET Transistors used as Switches How do we get them turned on? How do we know if we have been successful?

6. CMPE 118 MECHATRONICS What is CMOS ? Complementary MOS N-Channel and P-Channel used in Pairs

7. CMPE 118 MECHATRONICS What is CMOS ?

8. CMPE 118 MECHATRONICS Digital Inputs Logic Levels Voltage Levels 01 < Low Threshold > High Threshold

9. CMPE 118 MECHATRONICS What Are the Voltage Levels? That Depends on the type of logic... Transistor Transistor Logic High-speed CMOS High-speed CMOS, TTL input Original CMOS

10. CMPE 118 MECHATRONICS How is the Voltage Specified?

11. CMPE 118 MECHATRONICS It takes Voltage and Current to make a device work

12. CMPE 118 MECHATRONICS Inter- Connecting

13. CMPE 118 MECHATRONICS Bipolar TTL OutputDigital Logic

14. CMPE 118 MECHATRONICS Open Collector Output Digital Logic

15. CMPE 118 MECHATRONICS CMOS Totem PoleDigital Logic

16. CMPE 118 MECHATRONICS Sizing a pull-up Resistor: Max & Min.

17. CMPE 118 MECHATRONICS

18. 74HC04

19. CMPE 118 MECHATRONICS 74HC04

20. CMPE 118 MECHATRONICS Absolute Maximum Ratings Not so Useful Quite Useful

21. CMPE 118 MECHATRONICS Absolute Maximum Ratings

22. CMPE 118 MECHATRONICS Logic Levels and Noise Margins

23. CMPE 118 MECHATRONICS What about Slowly Changing Inputs?

24. CMPE 118 MECHATRONICS How do you get Hysterisis ? 1) Schmitt Trigger inputs 2) Comparator with Hysterisis

25. CMPE 118 MECHATRONICS

26. 74HC14

27. CMPE 118 MECHATRONICS The DarlingtonPower Outputs

28. CMPE 118 MECHATRONICS

29. DS3658

30. CMPE 118 MECHATRONICS DS3658

31. CMPE 118 MECHATRONICS

32. ULN2003A (1 of 7 per package)

33. CMPE 118 MECHATRONICS ULN2003A Specifications

34. CMPE 118 MECHATRONICS Not all 7 at once !